From 58352ea69d3e40bd3c91eacc7bbd48f58d5f2c8a Mon Sep 17 00:00:00 2001
From: Max Kellermann <max@duempel.org>
Date: Fri, 29 Aug 2014 23:22:46 +0200
Subject: [PATCH] db/Stats: use std::chrono::duration for the total duration

Use milliseconds precision to reduce rounding errors.
---
 src/Stats.cxx                          | 7 +++++--
 src/db/Helpers.cxx                     | 2 +-
 src/db/Stats.hxx                       | 6 ++++--
 src/db/plugins/ProxyDatabasePlugin.cxx | 2 +-
 4 files changed, 11 insertions(+), 6 deletions(-)

diff --git a/src/Stats.cxx b/src/Stats.cxx
index 8fc626ecb..39d371ace 100644
--- a/src/Stats.cxx
+++ b/src/Stats.cxx
@@ -99,15 +99,18 @@ db_stats_print(Client &client, const Database &db)
 	if (!stats_update(db))
 		return;
 
+	unsigned total_duration_s =
+		std::chrono::duration_cast<std::chrono::seconds>(stats.total_duration).count();
+
 	client_printf(client,
 		      "artists: %u\n"
 		      "albums: %u\n"
 		      "songs: %u\n"
-		      "db_playtime: %lu\n",
+		      "db_playtime: %u\n",
 		      stats.artist_count,
 		      stats.album_count,
 		      stats.song_count,
-		      stats.total_duration);
+		      total_duration_s);
 
 	const time_t update_stamp = db.GetUpdateStamp();
 	if (update_stamp > 0)
diff --git a/src/db/Helpers.cxx b/src/db/Helpers.cxx
index 8df6c265c..add4bb98e 100644
--- a/src/db/Helpers.cxx
+++ b/src/db/Helpers.cxx
@@ -41,7 +41,7 @@ StatsVisitTag(DatabaseStats &stats, StringSet &artists, StringSet &albums,
 	      const Tag &tag)
 {
 	if (!tag.duration.IsNegative())
-		stats.total_duration += tag.duration.ToS();
+		stats.total_duration += tag.duration;
 
 	for (const auto &item : tag) {
 		switch (item.type) {
diff --git a/src/db/Stats.hxx b/src/db/Stats.hxx
index 107af9d5f..131a5dc47 100644
--- a/src/db/Stats.hxx
+++ b/src/db/Stats.hxx
@@ -20,6 +20,8 @@
 #ifndef MPD_DATABASE_STATS_HXX
 #define MPD_DATABASE_STATS_HXX
 
+#include "Chrono.hxx"
+
 struct DatabaseStats {
 	/**
 	 * Number of songs.
@@ -29,7 +31,7 @@ struct DatabaseStats {
 	/**
 	 * Total duration of all songs (in seconds).
 	 */
-	unsigned long total_duration;
+	std::chrono::duration<std::uint64_t, SongTime::period> total_duration;
 
 	/**
 	 * Number of distinct artist names.
@@ -43,7 +45,7 @@ struct DatabaseStats {
 
 	void Clear() {
 		song_count = 0;
-		total_duration = 0;
+		total_duration = total_duration.zero();
 		artist_count = album_count = 0;
 	}
 };
diff --git a/src/db/plugins/ProxyDatabasePlugin.cxx b/src/db/plugins/ProxyDatabasePlugin.cxx
index 97b544203..8f9d12188 100644
--- a/src/db/plugins/ProxyDatabasePlugin.cxx
+++ b/src/db/plugins/ProxyDatabasePlugin.cxx
@@ -807,7 +807,7 @@ ProxyDatabase::GetStats(const DatabaseSelection &selection,
 	update_stamp = (time_t)mpd_stats_get_db_update_time(stats2);
 
 	stats.song_count = mpd_stats_get_number_of_songs(stats2);
-	stats.total_duration = mpd_stats_get_db_play_time(stats2);
+	stats.total_duration = std::chrono::seconds(mpd_stats_get_db_play_time(stats2));
 	stats.artist_count = mpd_stats_get_number_of_artists(stats2);
 	stats.album_count = mpd_stats_get_number_of_albums(stats2);
 	mpd_stats_free(stats2);